Lens-grinding machine



L. G. SIMPSON.

LENS GRINDING MACHINE.

APPLICATION FILED NOV. 30|1918.

1,41 5,6 1 3 Patented May 9, 1922.

INVENTOR ATTORNEYJ [507a SW50];

UMTED MATES gear caries.

LEON G. SIMPSON, OF ROCHESTER, NEW YORK, ASSIGNOR TO BAUSCH & LOMB OPTICAL COMPANY, 02E ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

LENS-GRINDING MACHINE.

To all who-mat may concern:

Be it known that I, LEON G. SIMPSON, a

citizen of the United States, residing at the city of Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Lens-Grinding Machines; and I do hereby declare the following to be a full, clear,-and exact description. ofthe same, reference being had to the accompanying drawings, forming a part of this speclficatlon, and to the reference numerals marked thereon.

My invention-relates t0 lens grlndmg machines of the class in which a lens blank is mounted on a lens carrier, and adapted to vcooperate with an abrading shell or lap. The object of my invention is to provide a detachable connection between the revoluble spindle and the lens carrier which will bepositive in action, economical to produce and free from lost motion. A further object of the invention is to produce a connection between the 'lens carrier and its supporting shaft, which will permit of a wide range of angularity between the support and the lens carrier without danger of displacing the lens carrier from the support, resulting in the injury or. destruction of the partly finished lens blank. A still further object of my invention is to provide a universal joint connection between the lens carrier and its support, which reduces chattering and consequent 1n ury to the lens blanks to a minimum. A more specific object of the invention is to provide a'detachable universal joint connection between the lens carrier or block and its shaft, which permits the lens carrier to be removed for examination of the lens during the grlnding operation. or for the insertion of a new lens, and inwhich the carrier has a free angular movement without binding as it moves on the lap to cooperate with any part of the surface of the grinding lap without binding, and while the supporting shaft for the lens carrier is maintained in substantially parallel relation with the axis of the grinding lap. To these and other ends the invention consists in certain improve-- ments and combinations of parts, all aswill be hereinafter more fully described, the

novel features being pointed out in the claims at the end of the specification.

In the drawings:

Figure 1 1s a side elevation of. a lens Specification of Letters Patent.

Application filed fiovember 30, 1918. Serial No. 264,849.

grinding machine, in which my invention the operating spindle being sectioned away.

Similar reference numerals refer to the same parts in all the figures in thedrawings.

In machines of this kind commonly employed for grinding lenses, a grinding shell or lap 1 is mounted on a shaft 2 in a bear.- mg 3, supported on a frame or bench 4. Means, not shown, are provided for revolv- 1ng the shaft 2 and the grinding shell mounted thereon.- laps are made detachable and interchange. able, so that shells having different curvatures may be employed for grinding lenses having different surface curvatures. Cooperating with the grinding lap is a lens block orcarrier 5, to which a lens blank 6 is secured by cementing or otherwise. A spindle or guide bar 7 is detachably connected with the lens block and is mounted in an overhanging arm .8, pivotally and rotatably supported by means of a yoke 9 on a post or other support 10. The overhanging arm 8 is provided with a handle 11 for manual manipulation, and may provide a housing for gearing adapted to transmit motion to the spindle 7 from a shaft 12 rotatably supported in the post 10. Motion is transmitted from the shaft 2 to the shaft 12 by means of a sprocket chain 13, which cooperates with a sprocket wheel on each of said shafts. However, it is to be understood that my'invention is equally applicable to machines in which the lens carrier spindle is "fixed in the overhanging arm and in which the lap only is revolved and in which the relative positions oflap and lens carrier are interchanged. When the arm 8-is moved in a horizontal plane, the lens blank on the carrier can be moved to cooperate with any desired part of the surface of the grindinglapg In order to insure perfect contact between the lens blank and the grinding lap in all positions of the latter, it is necessary to provide a universal joint connection between the lens carrier and its spindle. For the purpose of providing such a connection, which is free from vibrations causing chattering, and from which the lens block may be readily detached for the purpose of inserting a new lens blank, the lens block or carrier 5 is provided with a recess 15 in its upper surface. The recess 15 is elongated and extends nearly through the lens block. Seated in the recess is an elongated cylindrical bearing member 16 having an ellipsoidal surface in contact with the recess and rounded on the bottom.

.The bearing member 16 has a longitudinal groove or recess 17 into which the lower flattened end 18 of the shaft 7 extends. The shaft 7 is movably connected with the hearing member by means of a pivot pin 19, extending through the bearing member and the shaft near the bottom of the recess. It will be noted that by this construction, the bearing member has a large bearing surface on the lens block, and the pivot for the shaft is very near the grinding surface. The hearing member extends above its recess where it is provided with a cylindrical bearing surface 20 on each side of its slot, which are adapted to cooperate with bearing surfaces or shoulders formed on the shaft 7 adjacent the flattened end portion. This provides a rigid construction free from vibrations, having large bearing surfaces which materially reduce the friction. It will also be noted that in operation, the lens block is free to move in one direction on the bearing member and that the bearing member is free to move in another direction on the shaft. Itwill'also be noted that the bearing surface of the member 16 is very close to the upper surface of the lens, and that the pivot 19 is located as close to this bearing surface as possible, and that a free movement of the lens carrier through a comparatively wide angle is permitted without binding.

Although this inventionhas been illustrated and described embodied in a machine in which the lens carrier is supported by the pivotal arm with the abrading lap rotarily secured on the table, it is nevertheless obvious that the invention is also adapted to those machines old in the art having a reversal of parts in which the grinding lap is above the lens carrier and oscillatable.

I claim:

1. The combination of a lens carrier and a grinding tool cooperating therewith, one of said parts having a recess therein on the side thereof opposite the other of said parts, a guide bar and a universal joint between said recessed part and bar comprising a bearing member within the recess and rounded on the bottom for pivotal movement in said recess and a pin pivotally connecting the bearing member and guide bar within and adjacent the bottom of said recess.

2. The combination of a lens carrier and a grinding tool cooperating therewith, one of said parts having a recess therein, a guide bar and a socket joint between said recessed part and bar comprising a bearing member rounded on the bottom and contained within the recess for pivotal movement therein and a connecting means located within and adjacent the bottom of the recess pivotally joining said bar and bearing member.

3. The combination of a lens carrier and a grinding tool, one of said parts having a recess therein, a shouldered guide bar and a universal joint between said recessed part and bar comprising a bearing member rounded on the bottom for cooperation with the recess in said element and curved on top to engage the shoulder of said bar, and a pin pivotally connecting the bar and hearing member and affording an additional bearing surface between the bar and hearing member for relative movement therebetween.

4. The combination of a lens carrier and a grinding tool cooperating therewith, one of said parts having a bearing recess therein. a guide bar, and a universal joint between said recessed part and bar comprising an elongated bearing member disposed whollv within said recess and rounded on its bottom for cooperation with the bottom of the receSS by a transverse pivotal movement therein and a pin within and adjacent the bottom of said recess and connecting the guide bar with the bearing member for pivotal movement in a longitudinal plane of the bearing member.

5. The combination of a lens carrier and a grinding tool cooperating therewith, one of said parts having a bearing recess therein, a slotted bearing member within said recess, a guide bar for said recessed member having an end portion pivotally secured in the slot in the bearing member adjacent the bottom of the latter and within said recess. the bottom of said bearing member being rounded to provide for relative rotation between said recessed part and bearing member at right angles to the pivotal movement between the guide bar and bearing member, the top of the slotted portion of said hearing member being curved about said pivotal connection as a center, and a shoulder on said shaft in cooperation with said last mentioned curved portion of the bearing member to afford an additional bearing surface for axial thrust of said guide bar.

LEON G. SIMPSON. 

